[1287] added python wrapper

src/lib/python/isc/datasrc/iterator_inc.cc

@@ -31,4 +31,37 @@ the end of the zone.\n\
 Raises an isc.datasrc.Error exception if it is called again after returning\n\
 None\n\
 ";
+
+// Modifications:
+//  - ConstRRset->RRset
+//  - NULL->None
+//  - removed notes about derived classes (which doesn't apply for python)
+const char* const ZoneIterator_getSOA_doc = "\
+get_soa() -> isc.dns.RRset\n\
+\n\
+Return the SOA record of the zone in the iterator context.\n\
+\n\
+This method returns the zone's SOA record (if any, and a valid zone\n\
+should have it) in the form of an RRset object. This SOA is identical\n\
+to that (again, if any) contained in the sequence of RRsets returned\n\
+by the iterator. In that sense this method is redundant, but is\n\
+provided as a convenient utility for the application of the iterator;\n\
+the application may need to know the SOA serial or the SOA RR itself\n\
+for the purpose of protocol handling or skipping the expensive\n\
+iteration processing.\n\
+\n\
+If the zone doesn't have an SOA (which is broken, but some data source\n\
+may allow that situation), this method returns None. Also, in the\n\
+normal and valid case, the SOA should have exactly one RDATA, but this\n\
+API is not guaranteed it as some data source may accept such an\n\
+abnormal condition. It's up to the caller whether to check the number\n\
+of RDATA and how to react to the unexpected case.\n\
+\n\
+Exceptions:\n\
+  None\n\
+\n\
+Return Value(s): An SOA RRset object that would be\n\
+returned from the iteration. It will be None if the zone doesn't have\n\
+an SOA.\n\
+";
 } // unnamed namespace

src/lib/python/isc/datasrc/iterator_python.cc

@@ -132,10 +132,35 @@ ZoneIterator_next(PyObject* self) {
     }
 }
 
+PyObject*
+ZoneIterator_getSOA(PyObject* po_self, PyObject*) {
+    s_ZoneIterator* self = static_cast<s_ZoneIterator*>(po_self);
+    try {
+        isc::dns::ConstRRsetPtr rrset = self->cppobj->getSOA();
+        if (!rrset) {
+            Py_RETURN_NONE;
+        }
+        return (createRRsetObject(*rrset));
+    } catch (const isc::Exception& isce) {
+        // isc::Unexpected is thrown when we call getNextRRset() when we are
+        // already done iterating ('iterating past end')
+        // We could also simply return None again
+        PyErr_SetString(getDataSourceException("Error"), isce.what());
+        return (NULL);
+    } catch (const std::exception& exc) {
+        PyErr_SetString(getDataSourceException("Error"), exc.what());
+        return (NULL);
+    } catch (...) {
+        PyErr_SetString(getDataSourceException("Error"),
+                        "Unexpected exception");
+        return (NULL);
+    }
+}
+
 PyMethodDef ZoneIterator_methods[] = {
-    { "get_next_rrset",
-      reinterpret_cast<PyCFunction>(ZoneIterator_getNextRRset), METH_NOARGS,
+    { "get_next_rrset", ZoneIterator_getNextRRset, METH_NOARGS,
       ZoneIterator_getNextRRset_doc },
+    { "get_soa", ZoneIterator_getSOA, METH_NOARGS, ZoneIterator_getSOA_doc },
     { NULL, NULL, 0, NULL }
 };
 

src/lib/python/isc/datasrc/tests/datasrc_test.py

@@ -189,6 +189,20 @@ class DataSrcClient(unittest.TestCase):
 
         self.assertRaises(TypeError, dsc.get_iterator, "asdf")
 
+    def test_iterator_soa(self):
+        dsc = isc.datasrc.DataSourceClient("sqlite3", READ_ZONE_DB_CONFIG)
+        iterator = dsc.get_iterator(isc.dns.Name("sql1.example.com."))
+        expected_soa = isc.dns.RRset(isc.dns.Name("sql1.example.com."),
+                                     isc.dns.RRClass.IN(),
+                                     isc.dns.RRType.SOA(),
+                                     isc.dns.RRTTL(3600))
+        expected_soa.add_rdata(isc.dns.Rdata(isc.dns.RRType.SOA(),
+                                             isc.dns.RRClass.IN(),
+                                             "master.example.com. " +
+                                             "admin.example.com. 678 " +
+                                             "3600 1800 2419200 7200"))
+        self.assertTrue(rrsets_equal(expected_soa, iterator.get_soa()))
+
     def test_construct(self):
         # can't construct directly
         self.assertRaises(TypeError, isc.datasrc.ZoneFinder)
@@ -512,6 +526,17 @@ class DataSrcUpdater(unittest.TestCase):
         dsc.get_updater(isc.dns.Name("example.com"), True)
         self.assertEqual(orig_ref, sys.getrefcount(dsc))
 
+    def test_iterate_over_empty_zone(self):
+        # empty the test zone first
+        dsc = isc.datasrc.DataSourceClient("sqlite3", WRITE_ZONE_DB_CONFIG)
+        updater = dsc.get_updater(isc.dns.Name("example.com"), True)
+        updater.commit()
+
+        # Check the iterator behavior for the empty zone.
+        iterator = dsc.get_iterator(isc.dns.Name("example.com."))
+        self.assertEqual(None, iterator.get_soa())
+        self.assertEqual(None, iterator.get_next_rrset())
+
 if __name__ == "__main__":
     isc.log.init("bind10")
     unittest.main()